Depending upon the application, dual band or dual polarization concentric feeds are advantageous in illuminating lens or reflector antennas. For these types of antennas, concentric feeds are used so the system focal point is shared by both of the frequency bands or both of the polarizations. For high performance, the inner-conductive tube and the outer-conductive tube that make up the concentric feed require good electrical connection (electrical short) to each other in the region near the base of the feed. At high frequencies, where the feed parts are small, this important electrical connection is difficult to achieve in a consistent manner. If the electrical connection is not robust and repeatable, from a manufacturing standpoint, then the feed will have poor return loss resulting in increased mismatch loss and reduced antenna gain.